1. Field
The present disclosure relates generally to manufacturing and, in particular, to connecting structures to each other. Still more particularly, the present disclosure relates to a method and apparatus for connecting a stack up of structures to each other using a fastener system that includes a nut plate.
2. Background
In manufacturing objects, structures are often connected to each other. For example, in manufacturing an object, such as an aircraft, many different structures are connected to each other to form assemblies for systems in the aircraft. For example, skin panels may be attached to ribs and spars. As another example, floor panels may be connected to support structures in a fuselage to form the floor of a passenger cabin.
In connecting the structures to each other, different types of connecting systems may be used. One type of connecting system is a fastener system. A fastener system may include one or more fasteners. For example, a fastener for a fastener system may be a screw. In another example, a fastener system may be a bolt and a nut.
These fasteners are used to connect structures to each other. Holes are then formed in the structure. Next, nuts and bolts are installed relative to the holes.
In some cases, access to both sides of the structure may not be feasible. For example, automated equipment may not be able to access both sides of the structure to install fasteners. As a result, a human operator or additional equipment may be used to install the fasteners. In some cases, the location of the structure may make access to the inside fastening elements impossible.
One manner in which fasteners may be installed involves using a nut plate. A nut plate may be installed relative to a hole. The nut plate is configured to prevent movement of the nut element when the bolt is rotated. The nut plate is typically held in place through adjacent holes and rivets.
To reduce part count and installation time, rivetless nut plates may be utilized. Rivetless nut plates rely on friction to resist rotation in the hole. In composite materials, obtaining sufficient interference to resist rotation while not causing inconsistencies to the composite material may be difficult.
Therefore, it would be desirable to have a method and apparatus that takes into account at least some of the issues discussed above, as well as other possible issues.